Audiophonics HPA-S400ET Review (Stereo Amplifier)

[Bleib]

Like with all well-designed amps operating within their linear power-range: if you're not told what you're listening to, you won't be able to tell the difference.

Yeah, speakers, room, recording quality have more to say about the final outcome than well-designed amps

 

[Bob101]

Yeah, speakers, room, recording quality have more to say about the final outcome than well-designed amp

Purifi, or: How I Learned to Stop Worrying and Love class D​

 

[KaMatthi]

Hi to all, I am wondering about when the amplifier starts, a cracking noise can be heard from the tweeters. Do I have to worry?

 

[nemesis.ie]

Also try bypass mode and see if it changes?

 

[tmtomh]

If it's a quiet crackle that lasts one second that's normal when turning on a Purifi amp.

Agree. Mine makes a very low-level sound that lasts maybe 1/2 a second. I would describe it as sounding like a very tiny pop, although I suppose one could say it sounds like a much, much quieter version of the single staticky pop you get if you walk across a carpet in the winter and then touch something metal. I wouldn't call it a crackle because to me a crackling sound has to be longer than just momentary like that, but I could see how someone could describe it that way.

Not long after I got the amp, I emailed Audiophonics about it, and as @amper42 notes, they confirmed it's normal. The amp is silent when being turned off.

 

[AweLoi]

Hi to all, I am wondering about when the amplifier starts, a cracking noise can be heard from the tweeters. Do I have to worry?

I never had any noise like that with mine. If I put my ear close to the driver I can hear a short pop or klick when when I turn it on but it is a very quiet pop. I remember seeing a video somewhere with a guy with this problem. It seem like some have it and others don't.
Perhaps soldering a snubber cap on the power button will solve this?

 

[Salt]

It's a common issue and (though in this review) usually tested by ASR.
It means no harm for any speaker.
For me I can't remark any annoyance, as I'm used to the PLOPP at startup of amps produced on the Island in the '80th so don't bother.

 

[KaMatthi]

It's a common issue and (though in this review) usually tested by ASR.
It means no harm for any speaker.
For me I can't remark any annoyance, as I'm used to the PLOPP at startup of amps produced on the Island in the '80th so don't bother.

Thanks for letting me know. I was just wondering and had the fear my tweeters could harmed by that.

I have another question. My pre-amp is able to achieve 8V to the balanced output (Stormaudio MK2). What (Jumper) Configuration should be the best choice for me ( I bought the previous version, before 2023, from Audiophonics)?

 

[nemesis.ie]

I use bypass with the Altitude 32. If there is enough gain for you, that should give the lowest noise floor and least chance of tweeter hiss.

 

[KaMatthi]

But that means, the gain would be 12,8 dB... ideal would be 26dB?

 

[Salt]

I'm running low gain with RME ADI flawlessly.

Thanks for letting me know. I was just wondering and had the fear my tweeters could harmed by that.

I have another question. My pre-amp is able to achieve 8V to the balanced output (Stormaudio MK2). What (Jumper) Configuration should be the best choice for me ( I bought the previous version, before 2023, from Audiophonics)?

 

[magchiel]

But that means, the gain would be 12,8 dB... ideal would be 26dB?

Ideal would be the lowest gain (yielding lowest distortion) that gives you the desired SPL at listening position, given the input level from a source.
26dB I think spawns from the average consumer equipment (1.5-2Vrms SE) the average listening position (other may be able to provide a better historical or theoretical reference for this). And there's also THX's 29dB.
However since my RME ADI 2/4 can spit out +24dBu/12.24Vrms, the 12.8dB gain of the bypass setting is plenty to drive my 88dB/W/m speakers to a desired SPL at 290cm.

 

[AweLoi]

I have another question. My pre-amp is able to achieve 8V to the balanced output (Stormaudio MK2). What (Jumper) Configuration should be the best choice for me ( I bought the previous version, before 2023, from Audiophonics)?

With 8V I would go for 20dB or bypass. See recommendations here: https://www.audiophonics.fr/en/blog...udiophonics-purifi-and-ncorex-amplifiers.html

 

[Vhond]

Thanks for letting me know. I was just wondering and had the fear my tweeters could harmed by that.

I have another question. My pre-amp is able to achieve 8V to the balanced output (Stormaudio MK2). What (Jumper) Configuration should be the best choice for me ( I bought the previous version, before 2023, from Audiophonics)?

So there are different versions of the amp (before and after 2023)?? If yes what are the differences?

 

[nemesis.ie]

But that means, the gain would be 12,8 dB... ideal would be 26dB?

Ideal depends on your situation/input. For my system 12.8 dB gain is ideal - anything higher and I get tweeter hiss. Lower gain givea better SNR/SINAD per Amir's revirew, but if you have low sensitivity speakers and a low input level, the higher gains may be "ideal" for that case.

@Vhond The only apparent difference is the case and the jumpers are now accessible from underneath and have "finger tags" on them so easy to move.

They also have an LED defeat jumper but not (annoyingly) on the mono block model. See earlier posts.

 

[AweLoi]

So there are different versions of the amp (before and after 2023)?? If yes what are the differences?

One difference I know of is that in the old version you had to open up the amp to adjust the jumpers while they are accessible underneath the amp in the new model. The enclosure look a little different too. Don't know if there are any other major changes than that. I might have missed something.

 

[KaMatthi]

Ideal depends on your situation/input. For my system 12.8 dB gain is ideal - anything higher and I get tweeter hiss. Lower gain givea better SNR/SINAD per Amir's revirew, but if you have low sensitivity speakers and a low input level, the higher gains may be "ideal" for that case.

@Vhond The only apparent difference is the case and the jumpers are now accessible from underneath and have "finger tags" on them so easy to move.

They also have an LED defeat jumper but not (annoyingly) on the mono block model. See earlier posts.

I am going to change the jumper and listen to the difference. The StormAudio should be capable to handle the gain, hopefully. And my loudspeakers have a sensivity abou 88dB as well.

 

[nemesis.ie]

Remember you'll need to turn things up or re-calibrate too.

 

[KaMatthi]

I figured already. I replaced the new amp with an IOTAVX 7-230. They sound not much different. But what I can say of today. When I listening to music, I have fun to listen until the end, when I stopped with the other one to listen. Very nice… ThanKs to all for your help!!!

 

[nemesis.ie]

Are you saying you got rid of the Audiophonics from the system (without checking the gain jumper setting first?) and just put in a different amp?

I can see the appeal of 7 channels in one box, but other than that (and maybe the price) I'm not so sure why?

What's the gain of the IOTAVX I didn't see it obviously on their site.

Are you saying the 7ch one is less fatiguing than the Audiophonics one?